A temperature-dependent Raman spectroscopic study on Bi2 Zn OB2O6crystal was carried out to investigate the structure change of the crystal with the increase of temperature. Raman spectra of crystal Bi2 Zn OB2O6were r...A temperature-dependent Raman spectroscopic study on Bi2 Zn OB2O6crystal was carried out to investigate the structure change of the crystal with the increase of temperature. Raman spectra of crystal Bi2 Zn OB2O6were recorded in the spectral range 10–1600 cm-1at room temperature first. Compared with the vibrational spectra of the referred compounds,satisfactory assignment of most of the high-energy modes to vibrations of Bi–O, B–O, and Zn–O bonds was achieved. In particular, the Raman high-frequency peak located at 1344 cm-1was attributed to the B–O vibration in the BO3 triangle.This temperature-dependent Raman spectroscopic study was carried out up to 600°C. It was found that all the Raman lines exhibit decreases in frequency and the widths of the Raman peaks increase with increasing temperature. No phase transition was observed under 600°C.展开更多
通过水热法制备Bi2WO6、热分解法制备α-Fe2O3,并利用机械混合的方式获得α-Fe2O3/Bi2WO6复合材料。利用XRD、UV-Vis、BET、SEM、XPS对样品进行表征,相比Bi2WO6,α-Fe2O3/Bi2WO6复合结构在可见光区域的吸收带变宽。在α-Fe2O3/Bi2WO6+H...通过水热法制备Bi2WO6、热分解法制备α-Fe2O3,并利用机械混合的方式获得α-Fe2O3/Bi2WO6复合材料。利用XRD、UV-Vis、BET、SEM、XPS对样品进行表征,相比Bi2WO6,α-Fe2O3/Bi2WO6复合结构在可见光区域的吸收带变宽。在α-Fe2O3/Bi2WO6+H2O2光催化系统中,紫外光照射30 min MO完全降解;模拟太阳光照射60 min MO降解率达到85%,高于单独的Bi2WO6和α-Fe2O3。优良的光催化活性是由于光生电子从α-Fe2O3的导带迁移到Bi2WO6的导带,有效避免了光生电子-空穴的复合,从而提升了光催化效率;在α-Fe2O3/Bi2WO6+H2O2系统中,H2O2作为电子受体,H2O作为空穴受体,能够产生更多的羟基自由基,促进MO降解。展开更多
Although the traditional Fenton reaction is considered an effective strategy for solving problems caused by environmental pollution,construction of an efficient photocatalytic system by coordinating the Fenton reactio...Although the traditional Fenton reaction is considered an effective strategy for solving problems caused by environmental pollution,construction of an efficient photocatalytic system by coordinating the Fenton reaction is challenging.In this study,2D/2D step-schemeα-Fe2O3/Bi2WO6(FO/BWO)heterostructure photo-Fenton catalysts were successfully fabricated by a facile hydrothermal method.The as-prepared materials were characterized by XRD,FT-IR,TEM,XPS,UV-vis DRS,PL,I-t,EIS,and BET analyses.Under visible light irradiation,FO/BWO exhibited remarkably high and stable photo-Fenton catalytic activity for the degradation of methyl blue(MB)at low concentrations of H2O2.It was noted that FO/BWO(0.5)displayed a significantly enhanced photo-Fenton catalytic activity,which was 11.06 and 3.29 times those of FO nanosheets and BWO nanosheets,respectively.The notably improved photo-Fenton catalytic activity of FO/BWO was mainly due to the combination of H2O2 and FO under light illumination and the presence of the 2D/2D S-scheme heterostructure,with the large contact surface,abundant active sites,and efficient separation rate of photogenerated carriers playing contributory roles.Additionally,a possible catalytic mechanism for the FO/BWO composite was preliminarily proposed via active species trapping experiments.In summary,this study provided new insights into the synthesis of an effectively heterogeneous 2D/2D S-scheme photo-Fenton catalyst for degradation of organic pollutants in wastewater.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.50932005 and 51102239)
文摘A temperature-dependent Raman spectroscopic study on Bi2 Zn OB2O6crystal was carried out to investigate the structure change of the crystal with the increase of temperature. Raman spectra of crystal Bi2 Zn OB2O6were recorded in the spectral range 10–1600 cm-1at room temperature first. Compared with the vibrational spectra of the referred compounds,satisfactory assignment of most of the high-energy modes to vibrations of Bi–O, B–O, and Zn–O bonds was achieved. In particular, the Raman high-frequency peak located at 1344 cm-1was attributed to the B–O vibration in the BO3 triangle.This temperature-dependent Raman spectroscopic study was carried out up to 600°C. It was found that all the Raman lines exhibit decreases in frequency and the widths of the Raman peaks increase with increasing temperature. No phase transition was observed under 600°C.
文摘通过水热法制备Bi2WO6、热分解法制备α-Fe2O3,并利用机械混合的方式获得α-Fe2O3/Bi2WO6复合材料。利用XRD、UV-Vis、BET、SEM、XPS对样品进行表征,相比Bi2WO6,α-Fe2O3/Bi2WO6复合结构在可见光区域的吸收带变宽。在α-Fe2O3/Bi2WO6+H2O2光催化系统中,紫外光照射30 min MO完全降解;模拟太阳光照射60 min MO降解率达到85%,高于单独的Bi2WO6和α-Fe2O3。优良的光催化活性是由于光生电子从α-Fe2O3的导带迁移到Bi2WO6的导带,有效避免了光生电子-空穴的复合,从而提升了光催化效率;在α-Fe2O3/Bi2WO6+H2O2系统中,H2O2作为电子受体,H2O作为空穴受体,能够产生更多的羟基自由基,促进MO降解。
文摘Although the traditional Fenton reaction is considered an effective strategy for solving problems caused by environmental pollution,construction of an efficient photocatalytic system by coordinating the Fenton reaction is challenging.In this study,2D/2D step-schemeα-Fe2O3/Bi2WO6(FO/BWO)heterostructure photo-Fenton catalysts were successfully fabricated by a facile hydrothermal method.The as-prepared materials were characterized by XRD,FT-IR,TEM,XPS,UV-vis DRS,PL,I-t,EIS,and BET analyses.Under visible light irradiation,FO/BWO exhibited remarkably high and stable photo-Fenton catalytic activity for the degradation of methyl blue(MB)at low concentrations of H2O2.It was noted that FO/BWO(0.5)displayed a significantly enhanced photo-Fenton catalytic activity,which was 11.06 and 3.29 times those of FO nanosheets and BWO nanosheets,respectively.The notably improved photo-Fenton catalytic activity of FO/BWO was mainly due to the combination of H2O2 and FO under light illumination and the presence of the 2D/2D S-scheme heterostructure,with the large contact surface,abundant active sites,and efficient separation rate of photogenerated carriers playing contributory roles.Additionally,a possible catalytic mechanism for the FO/BWO composite was preliminarily proposed via active species trapping experiments.In summary,this study provided new insights into the synthesis of an effectively heterogeneous 2D/2D S-scheme photo-Fenton catalyst for degradation of organic pollutants in wastewater.
